Network interface devices (NIDs) are becoming increasingly popular in both residential and commercial applications. NIDs are electronic units used as an interface for providing telephone, media, and/or data services to a user. NIDs can be passive or active. Passive NIDs are generally used as a point of demarcation between a network provider's infrastructure and a home owner's wiring (for example, the telephone NID on the side of the typical home). Active NIDs contain electronic components which convert and/or process signals. For instance, NIDs include residential gateways, which are devices for receiving external telephone, media, and/or data services from providers. NIDs may, for example, receive fiber-to-home or fiber-to-curb connections and convert the signals sent by providers over these connections into a format, which can be utilized by a user device. A user device may include cable modems, set top boxes (STB), telephones, etc.
Powering NIDs, however, is problematic, because service providers generally prefer to place NIDs on the exterior of a building. This allows the service provider access to the NID without requiring access to the inside of the dwelling, but disfavored because placement of NIDs outdoors limits their access to electrical outlets. Even when NIDs are installed inside a building, they are often placed in remote locations, away from electrical outlets, due to the aesthetic concerns. Therefore, the placement of NIDs may often require the installation of wiring and electrical outlets, which is a time-consuming and expensive process.
The need to provide a battery back-up for NIDs further exacerbates the problem of powering NIDs. The battery back-up devices used to power NIDs in the event of a power failure are often large boxes, which provide further aesthetic disadvantages when placed inside a building. However, battery back-up devices cannot be efficiently placed outside a building in most locations because battery capacity and life are significantly affected by year round temperature fluctuations.
FIG. 1 depicts a prior art system 100 for powering a NID. The system 100 depicts a NID 102 located on the exterior of a wall 104 of a residential home. The NID 102 requires electrical power to operate, but there are no electrical outlets on the outside of the home within range of the NID 102. Therefore, the NID 102 must receive electrical power from an AC receptacle 110 located inside the home.
A primary power supply device (PPSD) 108 is connected to the AC receptacle 110. The PPSD 108 is a device operable to supply a DC current that may be used by the NID 102 as supplied power. The PPSD 108 receives an AC current from an AC source, such as the AC receptacle 110, and converts the AC to DC. The PPSD 108 may be plugged into the AC receptacle 110. The PPSD 108 also transmits the DC to a battery back-up device (BBD) 106. The BBD 106 transmits the DC power from the PPS 108 to the NID 102, during normal operating conditions, to thereby power the NID 102. The BBD 106 is a device containing a battery, which is operable to supply power to the NID 102 if the PPS 108 fails to provide a predetermined amount of power. For example, if the voltage received from the PPSD 108 drops below a certain level, the BBD 106 may provide power to the NID 102.
In the system 100, the NID 102, the BBD 106, and the PPSD 108 are connected in series, such that current flows in a single path through all the components. Typically, connecting the components in series requires installing newly installed wiring 112, because pre-existing wires are not of sufficient gauge to carry the required current to power the new equipment and/or are not present in a structure to connect a plurality of components in series. The newly installed wiring 112 may be installed in the walls or under the flooring of the structure having the NID 102; otherwise the newly installed wiring 112 must be left exposed. However, both possibilities are disfavored, because installing wiring is time-consuming and expensive and leaving the newly installed wiring 112 exposed may be aesthetically displeasing.